Ratchet mechanism



Feb. 33, 1923.

1,445,271 E. w. GENT RATCHET MECHANISM Filed Aug. 51, 1921 l/ve/enzorr'Lid aw 14/. Gena:

Patented Feb. 13, "i923.

it a. a it r it, it! ii ti EDGAR GENT, OE MOERISTOVJN, NEW' ASSIGIIOR TOVJESTERN ETIEC'I'RIC .GOI'EPANY, TNGQRPORATEDOF NEW YORK, N. Y.,COR-PURATION OF NEW YORK.

narcnnr MECHANISM.

To all whom it may concern:

Be it known thatl, EDGAR W. GENT, a citizen of the United States,residing at Morristown, inthe county of Morris, State of New Jersey,have invented certain new and useful Improvements in Ratchet Mechanisms, of which the following is a iiuli, clear, concise, and exactdescription.

This invention relates to ratchet mechanisms. 1

n An object of the invention is to provide a ratchet of the relativelynoiseless type with means for preventing itsoverthrow.

A, feature oi? the invention consists in the combination with a drivenratchet member of a driving pawl, means cooperating with the ratchetmember for positively moving the pawl into position to operativelyengage the ratchet member during the forward movement of the pawl andmeans for preventing overthrow of the ratchet. This means, in itspreferred form, comprises a lug integral with the driving pawl which isarranged to engage a fixed stop for moving the cam end of the pawl intothepath of the teeth of the ratchet member.

Figs. 1 and 2 of the drawing show the preferred form of the invention indifferent operating positions.

The ratchet wheel 1, as shown, is provided with six teeth, 1 1 1 1*, 11", and is secured to the spindle 2 and rotatable therewith. The member3 is preferably journaled on spindle 2 about which it is rotatable, andmay, for example be attached to or form a part of the finger wheel of anautomatic telephone calling device, such as that shown in U. S. PatentNo. 1,161,854, issued to O. F. Forsberg November 30, 1915. The membersat and 5 are each pivotedv on member 3 by means of pins 6 and 7,respectively and comprise an arm 8 which operates as a pawl and a camarm 9 which cooperates with the teeth of the ratchet to control itsassociated pawl 8. As illustrated, each pivoted membcr 4i and 5 subtendstwo ratchet teeth.

In Fig. 1, the member 3, together with the members 4. and 5 areindicated by an arrow as moving in a clockwise direction during whichmovement, as is evident, the ratchet wheel 1 remains stationary. The endof the pawl 8 of the member 4 is situated midway between the teeth 1 and1 whereas the end of the pawl 8 of the member 5 is disposed at the topof the tooth 1. The end of the arm 9 of the member 4:, which is suitablycurved, is seen to be engaged with the tooth 1 and it is evident that inthis position the end of the pawl 8 of the same member is in position toengage tooth 1 upon a movement in the direction indicated. in Fig. 2, inwhich figure said pawl is seen to have engaged the tooth 1 Now withreference to Fig. 1, let it be assumed that the member 3 is turnedthrough a considerable angle so that the pivoted members 4 and 5 passover several ratchet teeth. It is apparent from the drawing that eachtime the end of an arm 9 engages a ratchet tooth, the end of the pawl 8associated therewith will be moved toward the spindle 2, and accordinglyinto position to engage one of the ratchet teeth. It is also Y apparentthat the end of the pawl 8 in passing each ratchet tooth, moving in thedirection indicated in Fig. 1, will be moved out of engageable relationto the ratchet teeth. The pawl 8 of the member 5 in Fig. 1 illustratesthis last-mentioned condition. It will be seen that said pawl, afterpassing the tooth 1 will remain out of the path thereof until the end ofthe arm 9, associated with said pawl, is moved outwardly by the actionof tooth 1.

While the mechanism described comprises two pawls, it is not at allessential to the operation of the invention that more than one pawl beemployed. Thereason for using two or more pawls properly distributedwith respect to the ratchet teeth is to reduce the maximum distancewhich the member 3 would have to turn in the direction indicated in Fig.2 before one of the pawls engages the tooth. Such arrangement is commonin ordinary ratchet mechanisms, and does not constitute a part of thepresent invention.

Where it is desirable to stop the ratchet wheel immediately after thedriving member comes to rest, a fixed stop 10 may be provided to engagethe lug 1.1 which is preferably integral. with one of the pivotedmemhere, such as 4, upon which engagement the member 4L is rotated topress the curved end or cam portion of the arm 9 against the ratchetwheel, or preferably, against the back of one of the ratchet teeth. Thisaction immediately brings the ratchet 1 to rest.

In the appended claims, the curved end 1.71117 combination, atoothediratchet, a. member comprlsmg arpawl anda cam for.

cooperating with said ratchet and a'stop for engaging said member tothrowsaid ca minto engagement with said ratchet to prevent overthrowthereof. it

2. In combination, a ratchet, a bifurcated piyoted member, one arm ofwhich is a driving; pawl for said ratchet, and a stop 0 erabie to engageand rotate said pivoted member to movethe other arm thereof intoengagement with said ratchet to prevent overthrow of said ratchet.

3. In combination, atoothed ratchet meme her, a driving pawl,fo'rlsa'idiratchet memher, a fixed stop for limiting the movement ofsaid-gpawl and braking means operable by said stop to engage saidratchet member.

Inwitness whereo-fyl hereunto subscribe my name this 23rd day of AugustA. 1)., 1921

